In a typical cellular wireless communication system, such as a radio access network (RAN), an area is divided geographically into a number of cells and cell sectors, each defined by a radio frequency (RF) radiation pattern from a respective base station antenna. The base station antennae in the cells may then be coupled with a base station controller, which may then be coupled with a switch or gateway that provides connectivity with a transport network such as the public switched telephone network (PSTN) or the Internet. When a wireless communication device (WCD), such as a cellular telephone, pager, or wirelessly-equipped computer, is positioned in a cell, the WCD communicates via an RF air interface with the base station antennae of a cell. Consequently, a communication path can be established between the WCD and the transport network, via the air interface, the base station, the base station controller, and the switch or gateway.
Further, in some wireless communication systems, multiple base stations are connected with a common base station controller, and multiple base stations are connected with a common switch or gateway. Each base station controller may then manage air interface resources for multiple wireless coverage areas (e.g., multiple cells and sectors), by performing functions such as assigning air interface traffic channels for use by WCDs in the coverage areas and orchestrating handoff of calls between coverage areas. In turn, a switch and/or gateway may control one or more base station controllers and generally control wireless communications, by performing functions such as receiving and processing call requests, instructing base station controllers when to assign traffic channels, paging WCDs, and managing handoff of calls between base station controllers.
In general, air interface communications in each sector (or other such coverage area) of a cellular wireless communication system can be encoded or carried in a manner that distinguishes the communications in that sector from communications in adjacent sectors. For example, in a Code Division Multiple Access (CDMA) system, each sector has a respective pseudo-random noise offset or “PN offset” that is used to encode or modulate air interface communications in the sector distinctly from those in adjacent sectors. Analogously, in other air interface protocols, communications in one sector may be distinguished from those in other sectors by frequency, time, and/or various other parameters.
Each sector may define an air interface “access channel” on which WCDs can send “access probes” seeking to originate calls (e.g., voice calls, data sessions, and/or other “calls”) or seeking to register their presence in the sector. Further, each sector may define an air interface “paging channel” on which the serving base station can page a WCD. For example, paging channel may be used to send access probe acknowledgements and traffic channel assignment messages to served WCDs. The paging channel also defines timeslots in which the base station can send various messages to particular WCDs. For instance, if an access probe is received from one WCD seeking to connect to a second WCD, the base station may send a page via the paging channel to notify the second WCD of the incoming call.
If a base station has numerous such messages to send, however, the paging channel can become congested, which may delay call setup or even result in a page not reaching the intended WCD. Accordingly, in a further aspect of existing CDMA access networks, base station commonly group a certain number of pages (that are typically intended for different WCDs) into a common page message for transmission via the paging channel. Furthermore, to conserve bandwidth, and so that more pages can be transmitted per timeslot, each page in a page message may be concatenated.
Further, codecs may be utilized to encode and decode certain types of communications in a RAN. As such, a WCD may use various types of codecs to encode and/or decode voice calls, video calls, and/or other types of calls, when engaging in such communication. Further, the encoding associated with each codec may impact the amount of network resources that are used for a given communication. For example, communications that are encoded according to a first codec may use more traffic-channel bandwidth than communications that are encoded according to a second codec. Other examples are also possible.